A three-dimensional model has been developed to simulate the impact dynamics, heat transfer and solidification of a droplet onto a flat substrate. The model is an extension of the model developed by Bussmann et al. [1] and combines a fixed-grid control volume discretization of the fluid flow and energy equations with a volume tracking algorithm to track the droplet free surface and an improved fixed velocity method to track the solidification front. Surface tension is modeled as a volume force acting on fluid near the free surface. Contact angles are applied as a boundary condition at the liquid-substrate and the liquid-solid contact lines. Energy equations in the liquid and solid phases of the droplet are solved using the Enthalpy method. Within the substrate there is only conduction heat transfer. Thermal contact resistance at the droplet substrate interface is included in the model. We studied the deposition of tin droplets on a stainless steel surface using both experiments and numerical simulations. The results of two scenarios are presented: the normal impact of a 2.7 mm tin droplet at 1 mis, and the oblique impact of a 2.2 mm tin droplet at 2.35 mfs onto a 45° incline. The images obtained from numerical model are compared with photographs.

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